STAFF at Manchester Airport and airline workers were on alert looking for symptoms of a killer bug at the centre of an international alert.

Airlines based at Manchester - Malaysia Airlines, Singapore Airlines and Emirates, which all fly to the Far East - have been told to put their staff on alert.

Around a thousand cabin crew based at Manchester employed by British Airways have also been given the warning.

The alert follows the case of a Manchester man in his 60s who developed a flu-like illness after returning from the Far East.

The passenger was undergoing tests in the isolation unit of North Manchester General Hospital on Tuesday to see if he has been struck down with the mystery bug.

If the condition is confirmed, the Manchester man would be the first case of the illness to hit the UK.

The unnamed patient, who had recently flown back to the UK from Hong Kong, was taken to North Manchester General by paramedics wearing protective breathing masks from Wythenshawe Hospital yesterday after staff in casualty became concerned he was displaying symptoms of the mystery bug which sparked an international alert by the World Health Organisation at the end of last week.

The bug, known as Severe Acute Respiratory Syndrome or SARS, is described as a worldwide risk to health which is spreading fast from Asia to Europe via air travel.

It appears resistant to normal treatment.

Medical experts said the Manchester man - who has not been identified - was in a "stable" condition thanks to oxygen and intravenous antibiotics. The results of a number of lab tests on samples taken from him are expected on Tuesday.

Greater Manchester Health Protection Unit Co-ordinator, Dr Lorraine Lighton said: "We have alerted local health services to the importance of reporting any unusual illness which could be SARS, so that we can monitor the disease and ensure all necessary infection control precautions can be taken.

"Although there have been only a handful of cases outside the Far East we are taking the situation very seriously." The man travelled on KLM from Hong Kong to Manchester via Amsterdam on March 15.

The flights concerned were KL 0888 from Hong Kong to Amsterdam and KL 2037 from Amsterdam to Manchester.

A spokeswoman for KLM, Royal Dutch Airlines, said their staff were not aware that any passenger was feeling unwell during the two flights from Hong Kong via Amsterdam.

"After consultation with the Department of Health, KLM is urgently contacting passengers to suggest they seek medical advice," she added.

A BA spokesman said advice had been issued to its staff to watch out for unusual symptoms.